Production of carbureted water gas



June 5, 192s- C. W. ANDREWSy PRODUCToN OF CARBURETED WAT ER GAS June` 5, 1928. 1,672,109

c. W. ANDREWS PRODUCT-10N oF CARBURETED WATER GAS Filed. April s, 1922 2 Sheetsheet PRGDUGTIH F CARBURETEL* Appunti@ am Apri; a,

This invention relates .to gas production :md more particularly to a 'new and improved method for the production of suhszmtially nitrogen free gos from coal or simile?v fuels and to the enrichment of such lo the production of gos from coal, es now generally casi-led out, he process of manufaoui'e Consists of two distinct siepe,

4l The first step involves the production eolie from the owl with the acoompaoyiog removal of gas, tar and ammonia, The sec ond step involves the utilization of ehe eolie so omed in manuiaciure of 'Water ges.;

which may or may not be enriched oi corbummed. i

En the present practice, the first o1' eoliiog opeiotion is carried on in an ordinary retoilV which may he horizontal, inoiinec oi' l vetical, oi in some type of eolie oven. The esulting' colle is always more oi less cooled io 'transferring it, to a water gas generator with i'ssutan loss of hoot. A cersin amount of the coke gosied in ges; prodimers is consumed in heating iche reim-is or coke ovens although in the latier :i corresponding @mount of eolie oven gus is generali used in place of coke.

The ormatioo of miler 'gas in 'the gas o generator is accomplished by sitezimtely lasting oi' forcing air through the coke to briog it to o high temperature by means of combustion and then passing steam through the highly heated coke. During gche blasting oper-ation, blast gasesare formed which .are sometimes used io heilt waste-heet boilers,

During the seiiming operation9 blue waei 'gos isformed, @he sieem being broken down into hydrogen and oxygen, the latter unit ing with the gziibon of lhs eolie lo form osrhon monoxide. if ii is desired to enrich ilus blue Water gras, il may he passed lhiough :i eai'hureter, where oil is added `and thenthe oil and ges mixture may be passed through :i superhealei: iii order that the oil irony be fixed so that itwill remain in the :un not condense out in cooling. The blast are utilized to heat the carbureterable heat losses diie to the .removal of the ook@ from the retorts or @oke ovens and the toi' and superheaer, and., as stated above, in

the gasmsking FTENT `the expense in hoi'iiiliog she colse inoliifiixig "elle loss in breakage; also the broken is not os elli-cient in *bhe yenepatoi es he loegei' sise coke. A fort ier consideioble hea iossoeoors ohie io the fact ihm. he wze gos, is oimed at o Relatively high empemture and shoe the sensible hoot of lie gas is ooiJ utilized.

` i nulmhei' of ellos have been mode io completely g-asify cool 'in s. single eoritiou ons process. Nearly all such Ipi'ocessee siiipioy vertical i'eioithemhei siii''olmfied hy eheciaei-Woi'h ood. pla l above a genereior.' in opeisioo, i'esii ohai'ges of Coal are added periodically lo lhe top of the i'eort. The sir blast gases from the gos genesi-alor ore passed ihrough the cheeiieiwosli about the'ietort sind serve lo assist cokiig he ooal theein. .i v l During tho peiiods when steam is isii'oduced foi lie formation o he weer lhs. outlet of lhe eiieeler Chamber is closed emi', elle ootlev ai he *top oi lhe eior; is opeieel lo this way, the blue vater ges passes up. hi'ough she fetorf sweeps out he cool gos .sofi taz' fiom the coal and completes "ehe eosing. A. supeilieotei is sometimes added foi' the purpoo of fixing enrichiog msftei'isl which may added. e

l/Vhile his method offers :i process, it is, nevertheless, ooeo ber of oojooions. owing to the fact ihm, the haai of lie hisse gases is only partly utilized. Fossilien she production of in this process is very low. .An ooitionol objeofion lies in the .foot lili-ot :the blasting* period any ges, te?, ood ammonio, which may be oi'med in the fotoni cazo onlypsss out by Working down through @he Ajetort anal going .out wi'h the blast gases;

Atienxpts have been made' to produce ges continuously and with complete vgesiiemien of she fuel in a single unit by continuous blasting and. steaming', 'ous those sy'sems `necessarily produoe a gas hivh io Biologen fand of correspondingly low theat. 'mios The object of my invention is to iii-misco .o substantially nitrogemfree gas comme in ons ystem with complete 5 ill-ea iio?. he lw in the originel The 'e ,oienoy low all() Sli have been creased by utiiizing'heat from the hiue Water gas und blast grises for fixing enriching@ material added.

It is also an.ob)ect to provide o process Whichutilizcs the heat of the blast gases not utilized ini the watergasgencrotor for pro heating the air and stezmito increase correspondingly the temperature of the outgoing gases, both blost'iind blue, whereby 'tlie-tem. peruture of the blue gas Wiii be sufficiently high to curhoiiize the fuel as weli as to tix any enriching material, which mov he added.

It is si further object to provide e process wherein the -water gas generated is heated after its generzition,v the latter heating being preferably acomplishcd by passing the Water gas'through ues which have been heated `by the blast gas.

It is [en object to. provide e process wherein the sensible heat of the water ges produced is 'utilized in .the formation of colite, and wherein thewater gas is further utiiized to sweep out the coal gos lend tar :ind ammonio from the coal, and wherein then the heat of the gus aids in fixing the ter ond any other hydrocarbons which may loe addedn It is another object to provide a process utilizing the scnsibleheet of superhested blue waiter gas to heet walls around retorts to the extcn't necessary to positively coke 'the exterior of the material in 'the retort whereby sticking oi' the charge is minimized, ond thereafter utilizing the remaining sensible heet in the ges to complete the eolrin or the -luel. by passing directly through 'the tuel sind :it the same time on :icount of its voiiimc sweepinhr out thegos, tar, and ammonia, at u lower temperature than would be the crise if the 'fuel were heated from the outside.

Other and further objects will appear as the description proceeds, y

'lhc present application covers s process which is :L modification of that disclosed in my implication, Serial No. 542,342, ,tiled .Mln-elige, 1922.

In its brood aspects, my invention in volves tho use of 4sufficient units so that cosi is constantly being cokcd and Water g: s constantly -boiugr produced from' colte. permits a cyclic operation in such manner that each unit or cach set of units serves in turn as n curbonizing chamber and then es o. Water gos generator,

This .l

remise both biasting and making gas.'

in e preterahlednode of operatiomthe installetion involves three units operated in a `cvcle whereby throniighout the cycle, one unit :iets as a carhoniziog chamber and the other two units serve as Water gas generators, lilas-tuig and making gas in alteration, one

or the other et ali times'makng ga s, the. sensible heet of which gas is utilized 1n the' unit serving as e carbonizing chamber. The blasting is limited in amount and duration to the heat requirements of the process, sub stsntieily no product ofthe blasting period beingF mixed with the nitrogen-free product of this gas generating process.

lin order to Preheat the air and steam under the best conti-oi and in the most efficient manner, I prefereblpuse regenerative stoves in pairs, one stove for steam andtheother for air, such pairs beingiadopted to he sclez'tively associ-ated with anyottthe gas generating units.

An important feature of the method lies in the feet that the retort portion is heated by the Water gas so that substantially nitrogen-free gas isA on both sides 'of the 'iiue walls, that is, in the flues and inthe retort thus preventing degradation should there be any leakage through lthe flue wall. It is therefore, possible to usc any desirez pressure or 'suction in handling the gas.

DuringA its period of blast, each unit is' cn- A tirely cut oit' from the eoking unit and dur' ing its period of making blue Wster gas, no' blast gases are formed or possedgthroriglr such unit. f

A, further importaint feature of 'the method is the use of o cerhuretter and supc-rheater :tor crei-icing and tiring at the temperature best adopted for the purposethe condens- @bie vapors carried by the gas leaving the retorts, the heet for this being supplied from hlostgases in the usual Way.

A further importent feature lies in the fact that o. portion of the not bine gas con be direrted from Athe retort and sent direct t0,

the. corburetter, and superhester at a proper cracking temperature and there enriched by addition 'of tar or oil. i 4

I have iliustrated certain preferred embodiineni's of my invention in the accomponying drawings, in Which- Figure fis e4 rei-tieni section token on li'ro j liiggiire d' is a vhorizontai',setiti'onl teken OB A line f-i ont Figure 3; i

tine 5--5'or"l`igure 3; and

r ioure 5 is a horizontal section' ta'lrelrozil leither by :id-mixture of hot biueivater gosor ist Figure 6 is a horizontal section tekenen line S-vof Figure 4.' I

Referring now to Figures 1 and 2 of the drawings, the installation comprises tliree 5 similar gas" generating units A. E, and C.

As shown in Figure. 2. eacli unit comprises. a lower section 11 which serves a water gas generator. Each of these sections 11 has superposed thereon a coking retort seco tion 12 which in the construction shown,

comprises three separate retorts 13, 14 and 15. These retorts are surrounded and sepa.- rated by brickworlr carrying fines 16. A. circular passage 17 is formed at the lower end' 15 of the retort section surrounding such scction, .which passage, -is provided with ports 18 leadino to a chamber 19 located below the lower encv s of the ues 16 and in communication therewith. The passage 17 is connected by suitable pipes 20 with the bustle pipe 21 vvliich encircles the lower Water as section 1l. This bustle pipe21 bas leading tlierefroina plurality oi pipes 22 which lead to tuyres 23 discharging into the water gas 15 generator. The water, gas generator, as shown, isprovided with a grate bottom 24e and the pipes 25 and 26 lead into the asli pit below7 the grate bottom and are adapted for the introduction of' air and Isteam, re- 30,' spectively.

In the typical installation as shown in Figures 1 and 2, three lcomplete units similar to those just described are connected for conjoint operation. F lues 16 in each unit discharge into a space 27 at the top or" the The s ace 27 at the top of unit A is connecte to the similar space at the top of unit B by means of passage 28 and a similar pas-- sage 29 connects the space 27' of unit B with the similar space. 27 of unit C. A The by-pass passage 3() connects the passages 28 and 29 and serves to directly connect the spaces 27 of units A and C. This passage 30 is controlled by valve 31 adjacent passage 28 and '-15 by yalve 32 adjacent passage 29. The passage leadsrom the passage 28 to tbe stove l. The passage 28 is controlled between.`

unit A and passage 33 by means of valve 35 and between passage unit B ny l valve. 36. The passage 33 is cont-rolled by valve 37.

The stove K is connected by passage 38 with the stove L, the passage 88 being controlled by valve 39. A'passage Ll0 leads from stelle L to any heat recovery apparatus or to a stack of any usual type lfor dischargel of ,spent gases, the passage al) being controlled by valve al'. f\ L l's'llie air main il is connectedat142 to' l0 stove L. the connection 42 beingficontrolled bv valve 43. The stove L connectedfat M vvith the air header 45, the 'connect-ion being controlled by valve 46. The header connects to tne bustle pipe 21 of unit A, the conf .etfio n1/ing controlled by valve a7, and

.C tlie connection .water seal box 94, and the discharge pass similarly connects lo the bristle pipe of unit B, the connection being controlled by valve 48, and connects o'tlie being controlled by valve 49.

The passage 50 leads from passage 29 to stove M, this passage. 5!) being controlled by valve 5l. Tine passage 29 is controlled by ille valve 52 between unit C and passage 5() and by valve 53 between unit l and passage 50. The .stove M is connected to stove O by passage 54 which passage is controlled by valve 55. The stove t) .is connected to the air header 4&1, tbe connection being cont-rolled by valve 34. The stove O is connected at 5G with the air header et, the connection being controlled by valve 57. The stove O isfurther provided with tbe discharge passage 58 willich leads to the heat-apparatus or to the stack and' which is controlled by valve 59.

The' steam main' 60' is 'connected at G1 to stove M, tbe connection beingr controlled by valve 62 and at `(i3 to stove K, the connection being controlled by valve 6l. Stove K is connected to the steam header 65, the connection being controlled by valve 66, and stove M Yis similarly connected to the steam header, the connection being controlled by valve 67. The header (35 is connected at G8 to the bustle pipe "2l oi unitand is controlled adjacent said connection by valve 69. It is further connected to bustle pipe 21 of unit B at `70 and is controlled adjacent the iunction byvalve 71 andh is connected to bustle pi p trolled a jacent thereto by valve 73.

The passage n74 ,is located above thelretort section of unit A and is provided with openings 75 communicating with the upper ends of the several separate .ret/arts. This pas e 21 -of'nnit C at 72 and is conl bustle pipe of unit v all sage 74C leads to a commonA gas discharge passage 76 and is controlled before reaching said passage by valve- 77. 'The' passage 76 leads to an exhauster which4 may be used to create a suction in they system. The unit l is provided with 'a similar 'passage 7 8 provided with openings 79 communicating with the retorts of the unit,'tl1e passage also joining vtheA common gas discharge passage 7164 and being" controlled by valve 80. The unit' C is similarly provided with the passage 81 communicating with the retort sections thro hopenings 82 and controlled by valve 83 bei'ore its passage 76. k

The passage 86` leads from the passage 28, `(o tbe rcarblnetter'and superheatcr 87, the passage 8G being controlled by valve 88. The passage 89 controlled by valve 90 connects lthe superlicater with ille discharge vpassage 74. The pipe 91, conlrolled by valve' 92, leads into the carliuretter 8i'.

'point of junction with the v lIU The pas sage UB leads l'roin the carblirettcr to thev (T age from said box leads to the passage To.

by valve 102.

ing controlled by valve 96. The exhaust passage 9'? laads from the Carburettor to the stack 98, the passage being controlled by 'valve 99. till Similarly the passage 100 leads from the passage 29 to the carburetter and superheater 101, the passage 100 being controlled The passage 103, Controlled by valve 104 connects the superheater with the discharge passage 81. The pipe 105, eontrolled by valve 106, leads into the carbw retter 101. The passage 107 leads from the Carburettor to the water seal box 108, and the (liscl'iarge passage 109 from said box leads to the passage 76, being controlled by valve lll). rEhe exhaust passage 111 leads from the Carburettor to the stack 112, the passage being controlled by valve 113.

The passage 76 is controlled by valve lll at a point between the junction oi passages 74, 78 and 8l and the junction of passages 95 and 10S with the passage 76.

als

ln the operation ci my installation, itQ will be assumed, for ille purliose of lescription, that unit A is filled to a point ai proximately two-thirds ol the way up the ret/ort section'll, with coke. Unit B is ap proxilnately Completely iilleil with eolie andunit C has its lower water gas generating section l1 filled with colte and its upper retort section l2 filled with coal or similar fuel.

' a dash line.

bf course, that valves are closed,y and that valves 46, i8

`upwardly 'but also heating the The units A and Bare, in this portion of the cycle ol operation, each utilized for the production of water gas. Unit A is shown as on blast. The air for the blast is indicated in the drawing by a broken line consisting o dashes '.lhis air cornes through air main Ill4 and past valve Sel through the stove O into air header l.i5-'and past valve 4'3" into the bustle wipe 21 of unit A.. it is to be understood, and 59 oi' stove l) and 49 oi the air header are closed.

The bustle pipe 21 is connected by a pipe 2O to the passage 17 in the lower portion of vthe coke retort section and the valve 84e being open, a portion oil the air passes through the pipe 20 into the passage. The main body oi the air passes from the bustle pipe throughl pipes22 and is discharged through tuyres 23 into `the hot eolie in the Water gas generator section. This air blast raises the tern` perature of the eolie and the blast gases pass through the liue`16. The blast gases have been indicated in the drawing by lnfthe chamber 19 the blast gases are joined by the secondary air which comes up through the ports 18- from the passage 17. This secondary air joins with the blast gases to iroduee oonibustion in the lues, thus not ony heating the `eolie in the retort sections briekworlr of the lilies.

t is: to be luimlerstood that the passage ZV1 @coke in the retort.

seaarated b two dots.;

Laval-roe is closed ofi by valve end oi' the retorts is blanked oli', the" blast gases do not pass up through the mass of Supplemental air and steam may be introduced below the grate bot tom 24 through pipes 25 and 26, respeetively, il desired.

lhe blast gases pass from the lues 16 of. unit A out through passage 28 and a portion goes to passage 33 and thence through stove v 68 to stove L and throu hi and passage passage ll() to any suitable apparatus, or the further recovery of heat or to the stack. ".lhe valves 31 and 3G are closed to prevent passage of the blast ases to either' units 153 or l Valves 43 an 611 are closed tov prei7 andsinee the upper A vent passage of the blast gases to the steam orair mains, respectively, from" the stoves and Valves 46 and 6d are closed to similarly prevent passage of the gas to the air and steam headers.

rlfhe remainder of the blast gases .go through passage 86, valve 88 being open to superheater and carburetter 87 whi h serve to heat. sage 97 past valve 99 'and out stack 98. Valves 90 and 96 remain closed so that none ol the blast gases reach passages (4 and 76.

While unit A has been B has been making Water gas. The'steam has been indicated in the drawing by a line Comprising dashes soarated by three dots. The steam hasbeenintroduced from main through connection 6l ypast valve 62 into stove M where it has been super-heated. It thence passes through valve 67 to the steam header and past valve 71 from the header to the bustle pipe 21 or' unit B. It lwill be upon air blast, unit they'l The gases then out'pasunderstood" that the passages 50 and 54 leading from stove M, are closed by their valves 51 and 55, respectively. The steam header is closed oil from stove K by valve 66 and *from the discharge pipes o units A and C by means of valves 69 and 73, respectively.

The steam passes from the bustle pipe 2l of unit B through thepipes 22 and tuyres 23 and is introduced into the highly heated coke contained Within the Water gas generator. Additional steam may desired, through pipe 26 under the grate 24 as shown. The steam is, preferably, substantially at the temperature of the Water gas reaction and this reaction promptly takes place and Water gas is evolved w 1c gas passes up through the ilues have previously been heated by the pas sage of blast gases and this Water gas, during its passage, has itsy heat very considerably increased. f

84 controlling pipe 20 so steam run, the valve leading from the bustle pipe, 1s closed be introduced, it'4 flues 16. These y m5, It is to be understood that when on a coni or sof nincli Shorter minime tion closed and also the passage T8 is closed Valve Sid s that the Wetei"`gas does not tend to poss op through the eolie in the retorts. f' 2; y

The weiter gas hss neen indient-ed in the' ils-swings 'hy the loroZ i linel consisting of alternate .short end lo shes; The water; posses up three/gh noos le* onnit B, thence through psssnge 2Q to unit" C and downwardly through the fines 16 or" unit C. The retos-t sections of unit (l vere filled with Amiler fuel and the sensible heet u iis lsrgely einser-hed in the Wnllsof msssges 'f es :l e .retos ne erster ges es it leaves the es o the tides lo :is permitted s i ,f

upwardly through the tort ond thronjh re The veines l?. ,ssiy ststed, eiosed. lt od also 'selves 32 sind 5l 'tithe Water ges presses dii to enit pssssfge Si? Water gas new can in@ coni and eoiiidensehle vapors, dised from the enel inthe retort oi unit C,

l I BLESS dol.

passes through pss" lo?) pest valve llll to ureti r ,fniperheeter lill. `The is is cle e ssd prevents posseggo of the ons eet ,from gssssrigs @l to passage esrhnrett r9 oil, or any suiten'riehjng--msterinh my he edded pipe )t-95', valve 18S hei-ng opened for the purpose.' lrom the cerhnretter 101 esrhuretted -gss passes Waiter seni 108 and Athenee through passage to passage y the velve il@ being opened. The units A and are alternated en blast Sinne the hlest period is the-n the steam period. there periods 'when both units are matting weiter es. en' operation, liowever l he coordinated that there 1will he no pc iods when both units ere on'hlest. llins heated water is constaini'lj.Y supplied to the enit C. Where coking' is taking place. When both units and B are mais ing the valve 3 will he opened to pe'rmit 'the ira-,ter to from fines lt? oi unit .si unit B to unit C, or Valves 3l and may he opened to permit the gms to pass from unit A to unil C through passage will he eertsin 30. the former (fuse, vulve It? will he closed and in the hitter ense, Volvo 565. l't

will he readily apparent from the dizigfr-(in'i4 matic showing' of Figure l that when unit B is on hiss-t, its hhist gases will he passed through stoves L' and Cv and the unit will :receive its nir from ,stove L which hes previously hren limited from thil blast ro from :mit fi. livhen :mit A is on steam, it will receive iis. .dormi lhrongh stove it', which itis-clir hns heute-l during it hlzls't period.

The lion of the uni preferalol)v "het the (folie in unit A will (Ill l 'is lled through l0? to,"

`onethird of the height of' the section i:

that' time when the fresh fuel in unit C has ge been sufficiently coked. The operations in the several units are then changed for an other eriod in the cycle of operation. Unit u with fresh fuel and units B and C now alternate on steam and air, passing their bluewater gas through the flues of unit. A to eolie the material therein. It will thus he seen that the process is continuously eerried on and at the end lof. another period of this cycle, the coke in unit E, will he low-F f ered twosthirds or" the height of the retort section and that in unit C one-third of the height of the section, at which time the greenffuel in unit A will have heen coked. Unit B Will then be filled up with fresh fuel S' and will take its turn as the eoking unit of the installation, l VIt will be' understood that in the method.

of operation so far described, the carburetters and superheaters 87 and 101 will be nl. t"

temately heated by blast vgases and then used to heat blue 'Water gas `and tix enrichingr material during at least'a-portion of the stesm rum The enriching material may he tar or other material into the Carburettor orvmay be the coal end condensable vapors swept out of the coal in the eoking retort' section of a unit.` in. this method of operation, thatlportion of the water gas which is passed through the colo 10 host is required to :be supplied in the snper-v 11s heater. y Further during the firstand coole plotti tion or the steam run, theivqlatile matter swept out is large and may; be sufficient to constitute sary so that none need be added inthe superheater. Underi some conditions7 thismaterinl may he so great 'or of such' a character that it is not desirabltdx it but to condense it, or part of it,` out of the gas and m -the condensed material may be used for enriching a later portion of the run. -During thc later portion of the run, the volatile material swept. out of the `coal will be less `and there will he no'ohjection to adding enrichinpr inatclrial'in Athe Carburettor:

In another modified method ot' operation the necessary heat in the super-heater may he supplied entirely by blue Water gas and not hy blast gases,

introduced directly si? riod, some addiall the enriching material neces .Uf

or blast gases mey he im ,Water gas' during in-thegeneration Iof such gas, by

a portion olla'runand "blue the remain er of' the run. describedv herein,' the liluev utilized during As has been ully 'water gasfin my apparatus may be generated at a temperature materially above that usual means of usingpreheatedg'steatn, and' Further,-

1 the blue 'Watergas ris heatcdin the fines of Vthe unit,inwhnjzhl it is generated so thatl the blue waterjgas contains considerable sensil heating the coking retort of another unit;

ls This heat may be utilized by sending part- `l`of this method, some of water gasy output of the two units may be y heater while l' of the blue water gas As a further variation, 'Y may baisent to the same superheater to 'temperature of suchy gas With. y Y. -Under'some circumstances, due to varian.

vtion 'in therapidity of the dependent c operations, dus to diering conditi'ons,l materials cit-methods, it may loe de through the colo-ng retorto' another uniti' and sending 'the remainder through a superheater. l

As has'bee'n stated, due to the fact that the vblasting period is considerably less than"n the period of Water gas productlomihere'are considerable por 'ons ot' Working time when two units are bo l1 making u atei' gas. During such peixiodsyone unit may send its gas through the' unit making coke and then one superlieater While the other unit making gas will'send its'bluevwater gas directly to the other supe-rheater which is tiiyis heated by' the hot blue Water gas. As a variation the combined blue sent through the vchoking unitand one superthe remainder of the blue water gas goes direct to the other superheater.

sonieblue Water gas which' the water gas 'from the coking retort is being sent in order to directly raise the by mingling thereseveral intery Loraine siralole to add additional coke or coal to one or more of the units during diferent steps in the cycle of operations.

An important result oit the method of operation whereby in the colring unit, onethird of the retort section remains filled with coke, when it is illod up with a fresh charge of coal, lies in a largely increased produc tion oi ammonia. Tests have shown that passing Water gas through heated coke results in a avery pronounced additional yield of ammonia over other methods7 and my present inethod is adapted to accomplish this result. v

It is to lie understood that the apparatus shown is illustratlk'e'only and that 1n process" is not limited thereto butniay e-carried out by various other means. d intention to cover all modifications and Variations coming Within the spirit and scope of the appended claim.

I claim: l The process of producing mixed carbu retted water gas and coal gas, which comprises air-blasting carbonized residue to heatit, carrying ofty the blast gases through a heat absorbing structure surrounding a coking retort, passing steam into the heated residue to generate the water gas in the structure previously heated` hy the blast gases, passing the hot water figas lthrough coal in a separate coking retortL to yeolie and distill coal` contained in said retort, adding enaching material to the mixed Water gas and coal gas, and passing the mixture of gases cracking and fixing chamber while said gases are at a proper temperature for the eilicient cracking. of the enrichingl medi-um'and tine mixed gases.

thereby carburetting illinois, this 28th day Signed at (lineage,-- o llllarch, 1922.

' CHARLES W. ANDREWS.

through! a suitable It is hot water gas; heating 

